mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-06-26 22:38:30 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Reduce stack virtual memory consumption on Linux

Browse source
This commit is contained in:
Justine Tunney 2024-12-25 19:43:43 -08:00
parent cc8a9eb93c
commit 36e5861b0c
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
31 changed files with 583 additions and 166 deletions
Download patch file Download diff file Expand all files Collapse all files

38
libc/intrin/isqemu.c Normal file
View file

@ -0,0 +1,38 @@
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2024 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "ape/sections.internal.h"
#include "libc/calls/calls.h"
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/errno.h"
/**
* Returns true if process is running under qemu-x86_64 or qemu-aarch64.
*/
int IsQemuUser(void) {
static char rplus1;
if (!rplus1) {
// qemu doesn't validate the advice argument
// we could also check if __getcwd(0, 0) raises efault
int e = errno;
int r = !sys_madvise(__executable_start, 16384, 127);
errno = e;
rplus1 = r + 1;
}
return rplus1 - 1;
}